Increase in OC and folding ppd is not linear with power consumption in my experience. This is only tru up to the point were more OC'ing takes significant bumps in voltages to be stable. I have few/none that i run at stock VC.
Most Conroes and the most recent stepping pentium D's will achieve pretty high OC's without signiificant increases in volts. Increasing fsb will also increase your power draw even without increasing cpu volts. I have not seen a measurable effect of increased power draw through bumping v ddr, v mch, vfsb, etc. These comments are all based on my intel experience.
I use a ups with monitoring software to get a rough idea of power draw ... it reports in 6W increments. What i now realize tho is that i didn't measure any rigs fully loaded folding at stock speeds
. I guess i am such a points junkie that i didn't think the measurment was relevant
I did measure them OC'ed at idle. My main purpose in measuring them was to determine how many circuits i needed to run the folding farm.
With the doubly high costs in the hot months of both running the farm and the AC, i downclocked a few of the hottest running rigs and reduced VC. I also replaced some older smithfields and p4 ht's with newer stepping presslers to help contain electric costs without impacting production.
And now conroes not only improve production but also reduce the electric and cooling bill.